Butane is a colorless, flammable hydrocarbon with an empirical formula C4H10.
It has the odor of a natural gas, is extremely stable, has no corrosive action
to metal, slightly soluble in water and readily soluble in alcohol, ether and
chloroform. Butane is the fourth member of the alkane series (methane, ethane,
propane, butane, …). Butane is found in natural gas, light fuel oil or by
refining petroleum. Butane is a gas but is easily liquefied under pressure,
which makes it easy to transport. The hazards of butane are that it has a dangerous
fire and explosion risk.

Butane has two isomers. Normal butane is known as n-butane and isobutane is
methyl-propane. Like other alkanes n-butane and isobutene are short to react.
The isomers don't react with acids, bases and aqueous solutions. They also don't
form ions. With aid from a catalyst, butane or a mixture of butane and propane
can be oxidized by air under pressure to form methanol, acetic acid, acetone,
and other organic compounds. Currently, this is not a major use for butane but
it is said to be a promising technique for industrial synthesis.

Butane is typically used in the manufacture of aviation fuels and organic chemicals,
as fuel for cigarette lighters and portable stoves, a raw material for synthetic
rubber and high octane liquid fluids, manufacture of ethylene and solvent,
propellant in aerosols, a calibration gas for temperature and pressure gauges
and as a heating fuel. Butane is also added to gasoline in order to increase
its volatility (evaporation rate) in cold climates. Recent concerns about the
destruction of the ozone layer by freon gases has led to an increase use of
isobutene gas in refrigerating systems.

Energy density is a physics term for the energy per unit volume of a medium.
It is defined as joules per cubic meter or joules per kilogram. The energy
density of butane is approximately 27.76 MJ/L.